Field
Exemplary embodiments relate to a method for building a database for fingerprinting positioning and a fingerprinting positioning method using the built database. More particularly, exemplary embodiments relate to a method for building a database for fingerprinting positioning and a fingerprinting positioning method using the built database, which use a clustering scheme.
Discussion of the Background
Recently, with the increase in the use of smart phones, the market related to a Location Based Service (LBS) for providing various services using location information has rapidly grown. “LBS” refers to a location information-based system and service which comprehensively utilizes a mobile communication network and information technology (IT), such as a mobile phone or PDA. The LBS provides various pieces of information related to daily lives, such as product information, traffic information, and location tracking information, based on a customer's location information. The LBS is generally divided into Location Determination Technology (LDT), Location Enabled Platform (LEP), and Location Application Program (LAP).
Among the technologies, the LDT for determining the location of a device receiving the LBS corresponds to the most necessary technology for providing the LBS. Conventionally, the Global Positioning System (GPS), or a system using base stations for mobile phones, has been frequently used as the LDT.
However, GPS may generally have an error of up to several meters, and cannot determine a location in a shadow region, such as the inside of a building or a tunnel. Unlike GPS, the system using base stations for mobile phones can determine a location both inside and outside. However, because such a system is not very precise, the system can only approximately check in which block a device is located.
As a method for overcoming the imprecision of the GPS or the system using base stations and accurately measuring a location, a method using a sensor can be used, including the Radio Frequency Identification (RFID) or Ultra Wire Band (UWB) system. The UWB system has an advantage in that it can provide a precision as high as several centimeters with regard to indoor location tracking Thus, the UWB system is mainly utilized in a real-time location tracking system which requires location precision. However, although the systems exhibit high precision, the systems have a short transmit/receive distance, and require separate base stations for positioning. Thus, an enormous cost is inevitably spent in initially constructing the systems.
In order to overcome such problems, there is a need for a technology which exhibits relatively high precision and requires a small amount of extra cost for positioning. Recently, research has been actively conducted on a positioning technology using wireless access points (APs), which can satisfy such a need. That is because, since APs of wireless LAN (WLAN) for determining a location using wireless APs are already installed at a large number of places, separate base stations do not need to be additionally installed.
Such a positioning technology using wireless access points may be divided into two methods. One is a centroid method. This method receives Received Signal Strengths (RSSs) from three or more APs, and estimates a current location of a user.
The other one is a fingerprinting method. This method stores RSS data for each AP that are received from locations corresponding to a plurality of predetermined sample points (SPs). Then, when a similar RSS is measured, the method estimates the location of a user using the location of the corresponding SP.
However, the conventional fingerprinting positioning method has a problem in that, when the service area is widened, it requires a large capacity for storing RSS data. Furthermore, as the database is expanded, a search range is widened. Thus, an undesirably long period of time may be required for estimating a location.
The related art of the present invention is disclosed in Korean Patent Application No. 10-1390722, published on Apr. 24, 2014.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept, and, therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.